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β-FeOOH thin film was prepared on the surface of a foamed Ni substrate by liquid phase deposition (LPD) method with a chemical equilibrium reaction between metal-fluoro complex and oxyhydroxide to make a low-cost and environmentally friendly positive electrode for high-power batteries. The new film electrode, with a thickness of 316 nm, was found out to give a large discharge capacity of 260 mAh g−1 at 0.05 C rate even without an electro-conductive material. Furthermore, the electrode also showed good discharge performance with the retention of 69.9% at 10-0.05 C current rate, which means a promising positive active material for high-power use. 相似文献
134.
Electroinitiated cationic copolymerizations of indene-4-methoxystyrene and indene-β-bromostyrene monomer couples were investigated in dichloromethane by constant potential electrolysis. Copolymer compositions were determined by i.r. spectroscopy and reactivity ratios for the monomers were calculated according to integrated Lewis-Mayo equation. The composition of copolymers and the reactivity ratios were discussed in terms of anodic peak potentials of monomers. 相似文献
135.
The present study was carried out to examine the changes in functional properties of cholesterol-removed whipping cream by beta-cyclodextrin (beta-CD) treatment. The cholesterol removal rate reached over 90% in cream before whipping in all conditions (different stirring time and speed) applied. The apparent viscosity of beta-CD treated cream after whipping increased with increased stirring time and speed. Comparatively, the overrun percentage reached to 150%, and foam instability was measured as 2.5 ml deformed cream with lower stirring time (10 min) and speed (400 rpm). The thiobarbituric acid value of cholesterol-removed whipping cream increased from 0.08 to 0.14 stored at 4 degrees C during 4 wk; however, no difference was found compared with that of control. Above results indicated that beta-CD treatment process for cholesterol removal did not show a profound adverse effect on functional properties of cream after whipping. 相似文献
136.
We have investigated dry-etching properties of polycrystalline β-FeSi2 films formed by ion-beam sputter-deposition (IBSD) and the films epitaxially grown on Si by metal organic chemical vapor deposition (MOCVD) in order to realize fabrication of photonic crystals with several hundreds nanometers in dimension. Using reactive ion etching with magnetic neutral loop discharge (NLD) plasma, we succeeded in realizing a comparatively higher etching rate than that obtained by inductively coupled plasma (ICP). Both reactive ion etching and impact ion etching modes may contribute to etching of β-FeSi2. We have fabricated a two-dimensional photonic crystal of β-FeSi2 on Si substrates and confirmed its predicted photonic properties in a reflectance spectrum of polarized light. 相似文献
137.
We have investigated the preparation of β-FeSi2 substrate and growth condition of β-FeSi2 thin film on β-FeSi2 (110) substrate by molecular beam epitaxy. The surface of the substrate was prepared by a wet-etching using HF(50%):HNO3(60%):H2O = 1:1:5 solution at 25 °C. It is clear that the optimal etching period to obtain a flat surface was 3 min. The β-FeSi2 thin film with streak RHEED pattern was obtained at Si/Fe flux ratio of 2.9. Average surface roughness (Ra) of the β-FeSi2 film was about 0.5 nm in 5 × 5 μm2 area. 相似文献
138.
Large-sized β-FeSi2 substrates were successfully prepared for the first time from the silicide bulk crystal grown by the molten salt method. The structural, electrical and optical properties of the as-grown β-FeSi2 bulk crystals were also investigated. The crystal is single phase β-FeSi2, and polycrystalline with no preferable growth crystallographic orientations. It was also determined that the β-FeSi2 shows a p-type conduction, and the hole concentration and the Hall mobility at room temperature were about 1017 cm− 3 and 10 cm2/Vs, respectively. In addition, the PL emission around 0.8 eV was realized from the β-FeSi2 bulk crystal. This simple vacuum-free growth technique of β-FeSi2 and the large-sized substrate preparation procedure encourage us to develop future silicide-based electronics. 相似文献
139.
YU Zhou YANG Zhi-mei CHEN Hao WU Zhan-wen JIN Yong JIAO Zhi-feng HE Yi WANG Hui LIU Jun-gang GONG Min SUN Xiao-song 《半导体光子学与技术》2007,13(2):155-160
Ga2O3 nano-structures, nanowires and nanosheets are produced on Au pre coated(111) silicon substrates with chemical vapor deposition(CVD) technique. By evaporating pure Ga powder in the H2O atmosphere under ambient pressure the large-scale preparation of β-Ga2O3 with monoclinic crystalline structure is achieved. The crystalline structures and morphologies of produced Ga2O3 nano-structures are characterized by means of scanning electron microscope(SEM), X-ray diffraction(XRD), selected area electron diffraction (SAED) and transmission electron microscope(TEM). Raman spectrum reveals the typical vibration modes of Ga2O3 The vibration mode shifts corresponding to Ga2O3 nano-structures are not found. Two distinguish photoluminescence(PL) emissions are found at about 399 nm and 469 nm owing to the VO-VGa excitation and VO-VGaO excitation, respectively. The growth mechanisms of Ga2O3 nanowires and nanosheets are discussed with vapor liquid-solid(VLS) and vapor-solid(VS) mechanisms. 相似文献
140.
为了提高β-磷酸三钙(β-TCP)复合材料的机械性能,采用硬脂酸(C17H25COOH)对β-TCP表面进行改性处理,研究了β-TCP与C17H25COOH的界面作用机理.利用透射电镜、傅里叶红外光谱、热重分析等技术分别对改性前后β-TCP的颗粒形貌、组分和表面—OH基团进行了表征,研究了改性β-TCP/聚左旋乳酸(PLLA)复合材料的机械性能,并利用扫描电镜观察了复合材料断面形貌.研究表明:硬脂酸包覆在β-TCP表面,改性后β-TCP粉末具有一定的疏水性,硬脂酸的H+可以与β-TCP中的PO43-的一个O发生质子化反应形成—OH.改性β-TCP/PLLA复合材料的机械性能相比改性前有明显提高,改性后的β-TCP微粒在PLLA中分散均匀,两者结合紧密. 相似文献